Joint for compasses for measuring



UNITED STATES PATENT FFICE.

T. ALTENEDER, OF PHILADELPHIA, PENNSYLVANIA.

JOINT FOR COMPASSES FOR MEASURING.

Specification of Letters Patent No. 7,501, dated July 16, 1850.

To all whom t may concern Be it known that I, THEoDoR ALTENEDER, ofPhiladelphia, in the county of Philadelphia and State of Pennsylvania,have invented certain Improvements in Compass- Joints, and that thefollowing is a full, clear, and eXact description of the principle orcharacter which distinguishes them from all other things before knownand of the usual manner of making, modifying, and using the same,reference being had to the accompanying drawings, of which- Figure 1 isa view of the compass joint, Fig 2 a section, Fig?) the several partsseparated.

In the ordinary method of constructing the joints of Compasses ordividers for drawing instruments or other purposes, they are liableafter a short time to become loose; and to delay that period as long aspossible they are generally made at rst too tight and stiff. And thescrew with which thebetter class of instruments are made, is butA anim-` perfect remedy for such ditliculties. Besides the faults of suchinstruments, they are diiicult of construction requiring the mostskillful workmen to produce the requisite nicety of fit.

In my improved compa-ss joint I form the heads of the two halves (a, b)t-o fit with their flat sides together. The cap piece (c) lits looselyoutside of the pieces (a and b) and the center screws (el) havingrounding or conical ends, are screwedinward through the sides of the cappiece (c), and their points enter shallow holes of corresponding shapein the outsides of the pieces (a and b) which thuswork between centers,and are pressed together, with any degree of fric tion desired, and arecapable of the mostperfect adjustment. The set screws (e) serve toprevent the screws (d) from becoming loose.

Having thus fully described my improved compass joint, what I claim asnew therein and which I desire to secure by Let-ters Patent is- Acompass joint formed of two surfaces held together by center screwspassing through a cap piece, substantially asherein described.

THEODOR ALTENEDER.

/Vitnesses EDWARD EVERETT, T. C. DoNN,

